Until this week, I only had the 10 round Ruger mags for the wife's and my Mini-30's. With the scare of a ban before I could get a larger mag (last December), I scrambled to find hicap mags on the internet. The only place which I could find that had them available within reasonable time were the plastic magazines directly from Promag. They arrived this week, but they don't seem to want to clip in place very easily. The small hole in the muzzle side of the mag appears to be temperamental when trying to get the front pin to slide in and hold it in place. Occasionally I do get it to pop correctly in to place. But I have failed enough on it that their is now a small groove in the mag from sliding on that pin. Is this a common problem with Promag?